Basic and clinical studies for the targeting therapy by using the morphometrical analysis in malignant brain tumors.

改进的现代神经成像技术和坚固的固定系统可以在每次治疗时确定靶点相对于质子束的位置，基于质子束轨迹的治疗计划，每个解剖点处的剂量，基于准确评估每个像素的密度的团注等。我们研究所的质子治疗表明，患者可以耐受比常规放射治疗高15-20%的辐射剂量。而恶性脑瘤的治疗需140~160次TDF剂量，肿瘤体积小于10ml。因此，质子束将成为脑肿瘤形态计量学靶向治疗的主要手段。神经影像对临床上估计肿瘤的整体范围和边缘有很大的帮助。Gd-DTPA MRI可以有效地诊断治疗后肿瘤的存活率和恶性程度。此外，Tl-SPECT对于确定肿瘤的恶性生存能力似乎是有效的。在恶性肿瘤的超选择性1A化疗中，抗肿瘤药物进入肿瘤的平均速度为动脉内注射总剂量的6.3%。在计算ACNU给药剂量与肿瘤体积的比率时，可能需要平均320微克/毫升的ACNU作为有效治疗。DNA含量分析表明，恶性脑肿瘤具有不同的生物学异质性，其分析有待于形态计量学靶向治疗的进一步研究。

Improved modern neuroimaging techniques and rigid immobilization systems alow confirmation of the target position relative to the proton beam at each treatment, treatment planning based on beam trajectory, dose at each anatomical point, bolus based on accurate assessment of density along each pixel, etc. Proton therapy in our institute showed that the patient could tolerate radiation doses 15-20% higher than those of conventional radiation therapy used. However, it was suggested that the doses needed 140-160 TDF and the tumor volume was less than 10 ml to cure the patients with malignant brain tumor. Therefore, proton beam will be a main instrument of the morphometric targeting therapy for the brain tumors. Neuroimaging is very helpful in estimating clinically the overall extent of the tumor and the peripheral margin. Gd-DTPA MRI can be used effectively in the diagnosis of tumor viability and malignancy after treatment. Furthermore, ^<201>Tl-SPECT appears to be effective for determination of the malignant viability of tumors. In the effectiveness of superselective 1 A chemotherapy of malignant tumors, the antitumor drug was transported into the tumor at an average rate of 6.3% of the total dose injected intra arterially. In calculating the ratio of the delivered ACNU dose to the tumor volume, ACNU of the average 320 mug/ml might be needed as the effective treatment. From DNA content analysis, it is suggested that the malignant brain tumors have different bilogical heterogeneity and its analysis requires further study for the morphometric targeting therapy.